1002.] P. Finn — General Notes on Variation in Birds. 173 



A white form with the body and tail-feathers subterminally barred 

 with black in a very regular manner is not infrequent ; the primaries in 

 this are smoky-black on the inner and white on the outer web, not 

 barred as one would expect. Pure white, fawn, and grey varieties 

 occur in Europe, but apparently not in India. 



The legs of dark forms of domestic birds are horn-colour, not pink 

 as in the wild bird ; in light forms they are pinky-white. 



The occurrence of a downy crest iu tame Turkeys has been discussed 

 by Darwin ; I have never come across an instance. 



The tame Turkey shows a distinct increase in the size of the naked 

 head processes and carunculations as compared with the wild bird ; and 

 the tame Turkeys of India, as Blyth long ago remarked, similarly show 

 a marked increase of development of these parts as compared with 

 European domestic specimens. 



The feet are also coarser than in the wild bird. 



The Mute Swan (Cygnus olor) of Central Europe and Asia has been 

 tame for many centuries in Europe, but has practically lived the life of 

 a wild bird, largely shifting for itself, and often, when left unpinioned, 

 reverting to the wild state, so that its exact natural range is doubtful. 



The species has continued true to type except for the production of 

 one well-marked variety : — 



The Polish Swan (Cygnus immutabilis of Yarrell). In this the 

 plumage is white at all ages ; and the nestling-down is white. The feet 

 are flesh- or clay-coloured instead of black, and the frontal kuob is 

 smaller. Sometimes the cygnets are fawn-coloured in this form. 



The variety is known to be propagated truly for at least one genera- 

 tion. It has occurred iu a wild or feral condition, and has been bred from 

 the ordinary type both in England and of late years on the continent. 



Intermediate forms occur, for the characters are not sufficiently 

 constant to allow of this type ranking as a species, to say nothing of its 

 origin. Those few specimens which I have seen were, however, all 

 readily recognizable and typical. The variation is not recorded to bo at 

 all sexually limited. 



The Muscovy Duck {Cairina moschata) of Tropical America, was, 

 like the Turkey, found iu a domesticated state by the Spaniards, but it 

 also exists wild. 



Domestic birds are often nearly true to the wild type, but seldom 

 completely so, as they usually show a few white feathers about the head. 

 The head and upper neck are often grizzled throughout with black and 

 white, ending very definitely, while the rest of the body remains normal. 



Pied birds are common, the black being usually mostly restricted 

 to the crest, back, and tail, but the marking is not very regular. The 



